The present invention relates to a friction drive for playing discs. More specifically, the present invention relates to dual drive belt disc drive which rotates the disc.
In Japanese Patent Application No. 5-217033, the present applicant disclosed wrapping a single drive belt around a disc. When the belt was driven by an outside source, the disc rotated due to friction between the belt and the outer rim of the disc.
The above technology was utilized in Japanese Patent Application No. 5-316085, in which an independent drive source is used to move a disc through an optical beam of a stationary optical head.
A drawback of the prior art is that tension from a single drive belt applies uncompensated lateral pressure to the rim of a disc. This pressure may interfere with rotation of the disc, or dislodge it completely. A further drawback is that independent drive mechanisms are required for disc rotation and linear movement through the optical beam. The additional hardware and control systems needed to support two drive systems results in an increased size, complexity and cost.